Endografts with suprarenal fixation do not perform better than those with infrarenal fixation in the treatment of patients with short straight proximal aortic necks

OBJECTIVE

To determine if there are any differences in outcomes between infrarenal fixation (IF) and suprarenal fixation (SF) endograft systems for the endovascular treatment (endovascular aneurysm repair [EVAR]) of abdominal aortic aneurysms (AAAs) with short, straight proximal aortic necks (<1.5 cm).

METHODS

A retrospective review of 1379 EVAR procedures was performed between the years of 2002 and 2009 at a single institution. The charts and radiographic images of all patients were reviewed. Patients who underwent EVAR with AAA morphology with short proximal necks were stratified into two groups: IF, Gore Excluder (W. L. Gore, Flagstaff, Ariz) group and SF, Cook Zenith (Cook, Bloomington, Ind) group. The primary end point for the study was the presence of proximal type 1 endoleaks. Secondary end points were graft migration at 1- and 2-year follow-up and aneurysm sac regression. The groups' demographics and comorbidities were also compared.

RESULTS

A total of 1379 EVARS were performed during the study period and 84 were identified as having a short proximal aortic neck. Sixty patients were in the IF group and 24 in the SF group. The average follow-up period was 18.6 months (IF) and 18.5 months (SF). There was no difference in the average proximal neck length (1.19 cm IF vs 1.14 cm SF; P = not significant [NS]) or the preoperative AAA size (5.8 cm IF vs 5.9 cm SF; P = NS). There were no significant differences in age (76.6 years IF vs 74.8 years SF; P = .32), gender (IF 66.7% vs SF 21.88% men; P = .053), or length of stay (2.2 days IF vs 1.9 days SF; P = .39). The comorbidities (diabetes, hypertension, and warfarin use) were also similar. There were five type 1a endoleaks in group IF and one in group SF (P = .44) identified at the 1-month follow-up; however, only one patient in the IF group underwent intervention for enlargement of the AAA sac. At 1 year, there was persistence of one type 1a endoleak in both groups, but these were deemed dead-end leaks as they did not fill the sac nor lead to aneurysm growth. There were no migrations (>0.5 cm) noted in either group. Sac regression was observed at an average rate of 0.24 cm/year in the IF group and 0.26 cm/year in the SF group (P = NS). There were no aneurysm ruptures during the study period.

CONCLUSIONS

There are no significant differences in endograft migration or in the incidence of early and late type 1a endoleaks between endografts that use IF (Gore Excluder) and SF (Cook Zenith) fixation for patients with short aortic necks undergoing EVAR.

Incidence and outcomes after infolding or collapse of thoracic stent grafts

OBJECTIVE

Device-related complications in the thoracic aorta are partly due to the unavoidable proximal angulation and increased flow-related forces. The present study evaluated the incidence, predictors, and outcome of the complication of infolding with the GORE TAG thoracic endoprosthesis (TAG device) to better understand the factors that might help predict these events.

METHODS

We reviewed all complaints reported to W. L. Gore and Associates (Flagstaff, Ariz) related to device infolding after the use of the GORE TAG device on or before December 2008. Events related to device infolding were evaluated. Reporting physicians and local company representatives were contacted, when necessary, to assemble all available imaging, data, and outcomes related to these case reports. When available, computed tomography images were reviewed to confirm aortic landing zone diameters, which were subsequently compared with the implanted device size.

RESULTS

From 1998 through December 2008, device infolding was reported in 139 patients (mean age, 40 ± 17 years; 73.4% men) from 33,289 device implants (reported incidence, 0.4%). Events were noted in implants for trauma (60%), dissection (19%), aneurysm (10%), and other (9%) and unknown (2%) etiologies. In 77 patients with available imaging, the average minimum aortic diameter was 21.4 ± 4.4 mm. The mean device diameter was 28.5 ± 3.5 mm, with an average oversizing of nearly 33%. Of reported patients, 51% were asymptomatic, with the diagnosis being made on routine chest imaging. Time to diagnosis was 76 ± 222 days (median, 9.5 days). Only 16 patients received no intervention after the diagnosis of device infolding, all of whom were asymptomatic. The other 123 patients underwent 135 interventions. Of these, 30 patients (24%) underwent open surgical conversion and complete or partial endograft removal. The other interventions included a variety of endovascular techniques, such as large balloon-expandable stent(s) in 40%, relining with additional endograft(s) in 31%, and repeat ballooning in seven patients. Ten patients died after device infolding, all after one or more attempts to repair the infolded device: five died of symptoms related to the infolding and five secondary to the intervention undertaken to correct the device infolding.

CONCLUSIONS

TAG device infolding appears to be an infrequent event, primarily occurring in young trauma patients secondary to excessive oversizing and severe proximal aortic angulation. However, there clearly exists a need for devices that treat such patients. As a result, future device designs should consider the compression failure mode when being designed in order to help prevent such events.

Sex-based outcomes after endovascular repair of thoracic aortic aneurysms

INTRODUCTION

Unlike with abdominal aortic aneurysms (AAA), women appear to have an almost comparable incidence as men for thoracic aortic aneurysms (TAA). However, the extent to which a patient's sex influences endograft treatment of TAA has not been reported. The current study analyzes the influence of sex on the endovascular management of TAAs.

METHODS

A total of 421 patients (265 men and 156 women) were identified as part of the TAG (W. L. Gore and Associates, Flagstaff, Ariz) thoracic stent graft trials. Preoperative risk factors, intraoperative events, and 365-day follow-up data were analyzed.

RESULTS

Among 18 different preoperative risk factors evaluated, women were less likely to have prior vascular procedures (38.9% vs 55.3%; P = .004). A trend was noted toward lower rates of coronary artery disease (41.3% vs 51.2%; P = .09) and smoking (77.8% vs 85.6%; P = .08). Women were also more likely to be nonwhite (81.4% vs 87.9%; P = .007). Women had a smaller mean external iliac vessel diameter (7.1 vs 9.0 mm; P < .001), resulting in 24.4% vs 6.0% conduit use (P < .001) for device delivery. Local access site complications were significantly higher in women (14.1% vs 4.5%; P < .001). No difference was noted between sexes in the technical success rate (device delivery and successful aneurysm exclusion) or the major adverse event rate at 30 days (26.3% vs 20.4%; P = .18). The overall length of stay was 5.5 ± 6.2 days for female patients vs 4.8 ± 13.0 days (P < .001). No sex-related difference was noted in endoleak rate, aneurysm rupture, prosthetic migration, or aneurysm diameter change at 365 days.

CONCLUSIONS

No significant differences in major outcomes were noted between men and women treated with endovascular repair of TAA at 1 month and 1 year. Women have more vascular complications, which are associated with smaller access vessels. A lower threshold for using conduits in women may be a more prudent approach.

Thoracic aortic aneurysms and dissections: endovascular treatment

The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine.

Endovascular management of recurrent stenosis following left renal vein transposition for the treatment of Nutcracker syndrome

Nutcracker syndrome is an entity resulting from left renal vein compression by the superior mesenteric artery and the aorta, leading to symptoms of left flank pain and hematuria. Conventional treatment has been surgical, commonly through transposition of the left renal vein to a more caudal location on the inferior vena cava. Additionally, endovascular approaches, primarily via renal vein stenting, have been described for treatment of this syndrome. We report the case of a patient with Nutcracker syndrome who underwent successful left renal vein transposition but then developed recurrent symptoms 10 months postoperatively and was successfully treated with angioplasty and stenting.

Cerebral reserve is decreased in elderly patients with carotid stenosis

OBJECTIVES

Octogenarians and even patients over 70 years old have unexplained poor outcomes with carotid angioplasty and stenting (CAS). We sought to evaluate whether older patients may have compromised intracranial collaterals and cerebral reserve and be intolerant to otherwise clinically silent emboli generated during CAS.

METHODS

One thousand twenty-four cerebral blood flow (CBF) studies performed between 1991 and 2001 with stable xenon computed tomography scans (Xe/CT) were reviewed. CBF was measured before and after 1 gm intravenous acetazolamide (ACZ), a cerebral vasodilator. The normal response to ACZ is an increase in CBF. In areas of significant compromise of cerebral reserve (CR), CBF drops, representing a "steal" phenomenon. CBF changes were categorized as normal or abnormal and correlated with age, gender, cerebral symptoms, and with intracranial, carotid, or vertebral artery disease. Logistic regression was used to determine the effect of age on CR in the entire group and a subgroup of 179 patients with significant carotid stenosis of >50%.

RESULTS

Nine hundred sixteen studies were suitable for analysis. Carotid occlusion was predictive of decreased reserve (OR, 3.9; P = .03) regardless of age. There was also a trend toward lower reserve with severe carotid stenosis >70% (OR, 3) and in women (OR, 1.8; P = .08). Age >or=70 had no effect on reserve in the overall heterogeneous population with and without carotid disease and neither did a history of stroke, carotid, or intracranial stenosis. However, in 179 patients with significant carotid stenosis, age >or=70 was predictive of poor reserve (OR, 2.7; P = .03) and so was the presence of peripheral vascular disease (OR, 3.7; P = .03). A trend toward decreased reserve was also seen in women (OR, 2.3; P = .08).

CONCLUSIONS

Age >or=70 is associated with poor cerebral reserve in patients with significant carotid stenosis as measured by CBF response to an ACZ challenge. Thus, patients >or=70 may be more sensitive to minor cerebral emboli, which may be one factor explaining their higher risk of stroke during CAS.

Endovascular Repair of 2 Iliac Pseudoaneurysms and Arteriovenous Fistula Following Spine Surgery

Purpose: To describe endovascular repair of traumatic iliac pseudoaneurysm and arteriovenous fistula (AVF) following spinal surgery. Case Report: A 48-year-old male underwent minimally invasive L5-S1 hemilaminectomy, foraminotomy, and microdiscectomy spinal surgery for trauma related to a motor-vehicle accident. Postoperative angiogram demonstrated pseudoaneurysm of the right internal iliac artery and AVF at the common iliac bifurcation with the right iliac vein with prompt filling of the iliac vein and vena cava. The second patient, a 25-year-old female, underwent minimally invasive L4-S1 hemilaminectomy, foraminotomy, and microdiscectomy spinal surgery for intractable pain and was complicated with postoperative symptoms of congestive heart failure. Postoperative angiogram demonstrated AVF between the right common iliac artery and vein with associated pseudoaneurysm formation. Endovascular repair was performed in both cases. Follow-up imaging revealed no endoleak and complete pseudoaneurysm and AVF exclusion. Conclusions: Endovascular repair of iliac injuries following spine surgery can be successfully performed with minimal morbidity.

Vascular Wall Invasion in Neurofibromatosis-Induced Aortic Rupture

Neurofibromatosis type 1 (NF-1) is an autosomal dominant disease primarily characterized by cutaneous café au lait macules, benign neurofibromas, and iris hamartomas. A spectrum of vascular abnormalities is associated with NF-1. We present a case of a 49-year-old female with NF-1 and spontaneous rupture of the infrarenal aorta caused by invasion of a neurofibroma and treated with endovascular stent grafting.